COD Removal from High Salinity Petrochemical Wastewater Using Photo-assisted Peroxi-coagulation

• Published in: Chemical and Biochemical Engineering Quarterly Vol. 32; no. 2; pp. 229 - 238
• Main Author: Jorfi, S.
• Format: Journal Article Paper
• Language: English
• Published: Croatian Association of Chemical Engineers 01.07.2018; Hrvatsko društvo kemijskih inženjera i tehnologa; Croatian Society of Chemical Engineers
• Subjects: degradation; Fenton oxidation; high salinity wastewater; Oxidation-reduction reactions; petrochemical industries; Petrochemicals; Petrochemicals industry; photo-assisted peroxi-coagulation; Salinity; Sewage treatment; Wastewater
• ISSN: 0352-9568; 1846-5153
• DOI: 10.15255/CABEQ.2017.1268

Photo-assisted peroxi-coagulation (PPC) was investigated for treatment of high TDS (total dissolved solids) wastewater. The most important characteristics of the studied wastewater were high TDS of around 16428 mg [L.sup.-1] and [BOD.sub.5]/COD ratio of 0.07. Effective operating parameters, including initial pH values of 3-8, reaction time of 60-240 min, electrode distance values of 2-6 cm, and voltage values of 0.5-3 V were investigated in batch mode experiments. Optimum conditions were obtained at pH = 3, voltage = 1.5 V, electrode distance = 2 cm, and reaction time = 420 min, corresponding to 89.44 % COD removal, which meets the Iran environmental discharge legislation (COD = 100 mg [L.sup.-1]). Kinetic analysis showed that pseudo first-order kinetic model was best fitted ([R.sup.2] = 0.97). GC mass chromatograms before and after treatment showed degradation of complex compounds to more simple constituents. Keywords: photo-assisted peroxi-coagulation, Fenton oxidation, high salinity wastewater, petrochemical industries, degradation